Pirates 10, Padres 3: Jordy Mercer homered among his career high-tying four hits, drove in two runs and scored four times as visiting Pittsburgh routed San Diego in the opener of their three-game series.

Neil Walker went 3-for-4 with three RBIs while Josh Harrison added three hits and plated a run for Pittsburgh, which has won four of five. Charlie Morton (2-7) matched his career high with nine strikeouts while yielding two runs and three hits over five innings en route to his first win in six road starts.

The Pirates scored twice in the third inning on Mercer’s leadoff homer and Ike Davis’ sacrifice fly against Tim Stauffer (2-2), who exited after allowing two runs on 71 pitches through 2 2/3 innings. San Diego batters struck out 11 times and were held to five hits by four Pittsburgh pitchers.

Mercer singled in a run in the fourth to extend the Pirates' lead to 3-0 before San Diego answered with two in the fifth on Everth Cabrera’s RBI double and Seth Smith’s run-scoring single. The Pirates added a run on Walker’s RBI single in the sixth and sent nine batters to the plate in the seventh, when Harrison drove in a run with a single and Walker followed with a two-run double.

Pinch hitter Gaby Sanchez added a two-run double in the eighth for the Pirates, who recorded 16 hits and improved to 21-6 when scoring four or more runs. Andrew McCutchen, who has hit safely in each of his first nine career games at Petco Park, capped the scoring with a two-out, ground-rule RBI double later in the frame.

GAME NOTEBOOK: A total of six batters were hit by pitches – three on each team – setting a franchise record for a single game for San Diego. … RHP Jesse Hahn will make his major-league debut while starting Tuesday for San Diego, which had seven pitchers throw a total of 249 pitches in Monday’s contest. … The game lasted 4 hours, 4 minutes, setting a Padres record for a nine-inning home game.